direction,” Schwarzenbach points out. “The roughing wheel peels the material, it plows in there, and takes the material out. The finishing wheel travels a little behind to put the final finish on the part. The pinch comes from the fact that both wheels engage the workpiece simultaneously providing oppos- ing forces on either side to eliminate deflection or bending.” A rolling wheel pushes the spinning workpiece into a V block which provides support when the blank exits machining. Rollomatic has introduced a steadyrest attachment to catch long and thin parts that come out of the V block to pre- vent long and thin workpieces from whipping, which causes out-of-roundness and finish problems. Long thin parts up to 12" (305-mm) benefit from the steadyrest tailstock. Range of diameters of these parts is 1/8–3/8" (3.2–9.5 mm). Anything larger doesn’t whip, including ½" (12.7-mm) carbide.
Global Automotive Sets Standard
Cinetic Landis Corp. (Hagerstown, MD) prides itself on its expertise in the grinding of automotive components, in particular camshafts and crankshafts. Between it and a sister company in the UK, automotive and, increasingly, applica- tions from industrial compressors to diesel-powered off-road equipment are served with the latest orbital grinding designs. Products are designed and manufactured in-house based on proven machine platforms that have developed to cope with the rigorous demands of high-volume production, yet still be flexible enough to be used in batch production. Cinetic Landis products feature no-wear hydrostatic spindles and slide ways, with linear motor technology on all feed axes. The automotive industry where large V8 engines are largely
a thing of the past is trending toward universal adoption of 4- and 6-cylinder engines, with an emerging demand for 3-cylin- der power plants. New generation engines are smaller, requiring smaller components such as camshafts and crankshafts. This, coupled with a growing interest in more flexible equipment, has led Cinetic Landis to re-engineer its popular LT2 orbital grinder for global automotive manufacturers. The LT2E has the same capacity of the earlier design orbital grinder it replaces—shafts up to 750-mm long with a swing diameter to 180 mm—yet it uses less than half the floor space, has a lower more ergonomic centerline and incorporates smaller, more economical grinding wheels. The grinder’s twin wheelheads provide simultaneous grinding with wheels spaced as close as 20 mm. A continuing emphasis on process flexibility, coupled with a rapidly growing interest in energy efficiency in manufacturing
processes, has created a promising market for Cinetic Landis’ new EcoFlex traverse/plunge/contour grinder. Late in 2011, the company shipped the first EcoFlex grinder for use on a family of parts at a facility in Asia.
“The biggest challenges we face are meeting our cus- tomers’ demands for machine tools that are flexible enough to accommodate families of parts, yet be able to maintain and improve quality while optimizing process performance,” explains Tim Hykes, chief engineer. “We’re always looking at optimizing the process to be able to handle families of parts with different dimensions while making cycle times faster.” “What Tim is getting at is the fact that there’s a tradeoff in cycle time and reducing floor time in creating a flexible process,” says Dwight Myers, director of operations. “As the industry moves toward smaller batches of families of parts, customers we’re setting these production lines up for aren’t 100% sure what parts are going to be made on that line, sometimes even four to six months after they’ve ordered it. The new EcoFlex grinder is a machine platform that is
designed for handling larger parts for mining and heavy- industry applications like compressors for refrigeration where the challenge again is to consolidate manufacturing and be flexible. Cinetic Landis addressed two key issues—flexibility and economy of ownership—in designing the Ecoflex line of traverse/plunge/contour CNC grinders. The modular platform can accommodate either conventional aluminum oxide or superabrasive CBN grinding wheels. It incorporates a B axis that allows using multiple spindles and programmable angles to handle combined operations in a single fixture for better geo- metric accuracy. Linear motor drives are incorporated for the grinding wheel in-feed as well as the traverse axis to eliminate stick-slip positioning limitations. Target parts include large rolls, drive shafts, and similar large components. The base machine is targeted for parts up to 1.5-m long and 400-mm diam with a 750-mm part swing available as an option. ME